Integrated circuits are formed from a wafer or substrate over which are formed patterned microelectronics layers. In the processing of the substrate, plasma is often employed to deposit films on the substrate or to etch intended portions of the films. Shrinking feature sizes and implementation of new materials in next generation microelectronics layers have put new requirements on plasma processing equipments. The smaller features, larger substrate size and new processing techniques, such as dual damascene etching technique, require precise control of the plasma parameters, such as plasma density and uniformity across the substrate, for better yields.